The one thing everybody is talking about in the presidential race is the one thing we cannot truly know, and that's who's going to win.

INSKEEP: Some Republican pundits have boldly forecast a massive win for Mitt Romney, though they struggle to show exactly why.

MONTAGNE: Political odds-makers have made President Obama the favorite to win tomorrow's election, citing his narrow lead in key states, and also in recent days, his narrow lead in most national polls.

INSKEEP: But even the odds-makers admit there is a chance the president could lose. While we wait for results, Cokie Roberts and Mara Liasson have been watching the campaigns' final days. They're both with us. Good morning to you both.

MARA LIASSON, BYLINE: Good morning.

COKIE ROBERTS, BYLINE: How are you doing?

INSKEEP: I'm fine.

MONTAGNE: And you - Cokie, Mara - put this to both of you. National polls first, polling averages that showed Mitt Romney just a little bit ahead now show him just a little bit behind. How much have things changed?

ROBERTS: Not a whole lot. This has been a tied election from the beginning and it's basically still a tied election. The president up maybe one point, but this is all within statistical margin of error. This is - I mean all these many months and many dollars spent, we are still where we started with a basically tied election.

INSKEEP: Go ahead, Mara.

LIASSON: Yeah. And you know, the other thing that strikes me really is that we seem to be seeing two parallel universes. When you look inside some of those national polls you see a lot of danger signs for an incumbent. The president is losing white voters by much bigger margins than he did in 2008, and independents. Republicans might have an enthusiasm edge.

But then when you look at the polls inside the battleground states, those problems just don't seem as severe for the president. And that's probably one of the reasons why he's maintaining a tiny but pretty steady edge in those seven states where the candidates are spending all their time and money.

INSKEEP: Well, I'm glad you mentioned those states, Mara Liasson. As people know by now, you don't win by winning the popular vote. You win the presidency by winning 270 electoral votes, decided state-by-state. I've been playing actually as NPR.org with this Swing State Scorecard, where you can pick your own victors of different states and try to figure out ways that each candidate could add up 270 electoral votes.

Now, when you look at each candidate's position, who has more paths to get to 270?

ROBERTS: Oh, the president definitely has more paths to get to 270. Mitt Romney needs to win more states that are not heading in his direction right now to get to 270 than the president does. But having said that, I mean there's nothing you can say with this election cycle that you don't have to then couch. And having said that, you know, the place that the president has been placing a lot of his hopes is Ohio.

Now, he can win without Ohio but that is - that's a tricky place to place your bets. Mara, you've lived through that one before.

LIASSON: Well, yeah. And Romney seems to have a much harder time living without Ohio. And I think that's one of the reasons why you saw him go to Pennsylvania yesterday. That's a traditionally blue state but one where the polls have really - the gap between the two candidates has really shrunk in recent weeks, and he wanted to expand the battleground. Because if he can't win Ohio, he needs another really big state to replace it with.

ROBERTS: And that gets to that question that Mara was just talking about - white voters. I mean we really are looking at two universes here. Romney is doing well with whites - particularly white men, and particularly married - married white men who didn't get a college education. That's his biggest vote.

And you go to someplace like Pennsylvania and there are whole lot of white men there, and a whole lot of old people there. And that's also been a vote that has not gone for the president the last time and doesn't appear to be going for him this time. But there's also a whole lot of Democrats there. And so that becomes the problem for him.

LIASSON: Yeah, I mean I think Democrats still have close to a million-vote registration advantage in Pennsylvania.

INSKEEP: Well, you talk about the whites vote. Of course the president is hoping to offset that with a minority vote that they're expecting to be huge again this year, and perhaps win as much as up to 80 percent of the minority vote. I guess the question is whether that's enough to offset the president's losses among the white vote.

MONTAGNE: And especially, let me put in, the Latino vote. That's quite the big thing this year, and is something that we're paying a lot of attention to.

ROBERTS: And the answer to the question of whether it's enough is turnout - what percentage of the electorate will be non-white? In the last election it was 26 percent. There's an expectation that it could be as high as 28 percent in this election, and if the president wins 80 percent of that 28 percent, particularly since it is in important states like Florida, like Nevada, like Colorado, then that could do it.

INSKEEP: Well, let me talk through one other thing. We've heard from the campaigns in recent days their scenarios of how they're going to win. They've been very determined in pushing that out. Neither candidate wants to have the impression created that his guy is going to lose. But talk me through, if you can, the nightmare scenario, if you will, for each candidate. These guys each must have in their mind the thing that could happen that could cost them the election. What is it?

COKIE ROBERTS: Well, certainly for the Obama campaign it's that Romney's - the Romney team's claims of organic enthusiasm just become too overwhelming. You know, a ground game and a get-out-the-vote operation which the Obama team has been working so hard to build for five years - and they've got a really sophisticated one - that matters in a very close election, but it can't surmount a kind of last minute wave for a candidate. And the Romney team has said they have organic enthusiasm. They have passion on their side and that's going to overcome, that's momentum.

ROBERTS: And that's going to overcome the president's advantage in a ground game. We haven't seen that necessarily in the polls recently, and as a matter of fact, some prominent Romney supporters like Haley Barbour and Karl Rove have already blamed Hurricane Sandy for blunting Romney's momentum at the end because it took the spotlight off the presidential campaign, at least briefly.

INSKEEP: Oh, does that get them off the hook for the predictions that Karl Rove in particular has made of...

(LAUGHTER)

ROBERTS: It might, it might. You know, it's an act of God. But you know, the other thing that Sandy could have done is intensify this question of whether one candidate wins the electoral college and another the popular vote, because if I'm in New York, here in New York people don't get to the polls or some of the polling places are closed, same thing in New Jersey, Connecticut, these are big Democratic states.

ROBERTS: And if the vote totals are held down in these states because of the continuing post-Sandy difficulties, that could make a difference in the totals of how many votes the president gets in states where he wins the electoral vote.

LIASSON: Yeah, talk about a nightmare scenario, that would be one of them, because yeah, it's easy to get the polls in Texas and Mississippi and Alabama. Not so hard in New York and New Jersey.

MONTAGNE: What you're saying, though, suggests something people have been talking about, and that is we will not know who the winner is on Tuesday night or even by Wednesday morning.

LIASSON: Possible...

(LAUGHTER)

LIASSON: There are so many weird things that could happen other than getting a clear winner on Wednesday morning. I mean there are so many - what if there are so many provisional ballots in Ohio and you're not even allowed to count them till later in November? There are also automatic recount laws now in several states where if the gap between the two candidates is smaller than .5 percent or .25 percent, there's an automatic recount.

ROBERTS: And there were already legal issues being raised in Florida over the weekend because of early voting laws and Democrats successfully suing to get polls open yesterday in several counties. But that could be a nightmare. I mean can you believe it? Florida could once again be a nightmare.

INSKEEP: Well, we've just got a few seconds left, but just to be - and we should be clear that the odds of some kind of catastrophe like that are still considered relatively low, but even after all the billions of dollars that have been spent, is it safe to say that both of these campaigns have reserved a little money for thousands of lawyers if they're needed?

ROBERTS: Oh, yeah.

LIASSON: You bet.

ROBERTS: Oh, yes. And even after the billions of dollars, the House and Senate likely to remain pretty much the same.

INSKEEP: Oh my goodness. Okay, well, thanks very much as always. That's Cokie Roberts, who joins us most Mondays here on MORNING EDITION, also NPR national political correspondent Mara Liasson. Both of them will continue to be part of our election coverage as we head toward November 6, tomorrow. You're listening to MORNING EDITION from NPR News. Transcript provided by NPR, Copyright National Public Radio.